The Seeds of Hope

By staff | January 1, 2004

First the good news. According to the American Cancer Society (ACS), the survival rate for prostate cancer has risen from 67 percent 20 years ago to 97 percent today. Now the bad news. It's still the most common form of cancer in men, second only to lung cancer. The ACS... Read more »

First the good news. According to the American Cancer Society (ACS), the survival rate for prostate cancer has risen from 67 percent 20 years ago to 97 percent today.

Now the bad news. It's still the most common form of cancer in men, second only to lung cancer. The ACS estimates that more than 200,000 men will develop the disease this year, and of those, nearly 30,000 will die from it.

Yet many men still avoid seeing their doctors about prostate problems because of the awkward-but necessary-physical examination. That's too bad, because what you don't know about prostate cancer can hurt, or even kill you. What you do know, and the earlier you know it, can save your life.

"The longer you live, the higher the probability you will get prostate cancer," says Dr. Alan Porter of Radiology Oncology Centers in Sarasota. And numbers from ACS bear him out; 70 percent of all prostate cancers are found in men who are 65 years or older. But anyone with a first-degree relative (like a father or uncle) who has had prostate cancer is at risk, as are most African-American men.

The National Cancer Institute discounts studies that implicate vasectomies, sexually transmitted disease, smoking or obesity in prostate cancer, but one possible cause is shifting hormonal levels akin to those that cause menopause in women. The American diet may also be at fault. In Japan, for example (and other populations with plant-based diets), the disease is rare. Yet second-generation Asians who come to the United States have the same occurrence of prostate cancer as American men. (The disease seldom strikes Native Americans.)

Symptoms include frequent, painful or urgent urination, especially at night. Some men experience painful ejaculation and blood in the urine or semen. There may also be pain or stiffness in the lower back, hips or upper thighs.

And no imaging system can detect this cancer. "The breast has mammograms, the lungs have CT or X-ray," says Porter, who performed the first seed implant therapy here in Sarasota in 1978. "Not in the prostate."

Not even state-of-the-art positron emission tomography (PET) is useful here, he says. "PET relies on the cell's consumption of sugar, but the prostate doesn't metabolize sugar. There are new imaging agents that will image the prostate, but they're not available yet."

Until then, the best tool to detect prostate cancer is a prostate-specific antigens (PSA) blood test. And if you're a man over the age of 40 who hasn't asked your doctor for this simple blood test yet, get on the horn today. "We should be so lucky to have such a test for breast or lung cancer," Porter says.

If a rectal exam finds something suspicious, and a blood test detects PSA levels above four, your doctor will order further tests, including an ultrasound (which can detect "echo changes" that may signal a malignancy) and X-rays. If the doctor suspects cancer, a biopsy is ordered.

If cancer is found, a patient has several options. The most traditional is surgery to remove the prostate in a procedure called a radical prostatectomy. After surgery, patients must wear a catheter for up to three weeks. The rectum can sustain permanent damage, and since the prostate is the gland responsible for producing semen, patients who do not store their semen beforehand can no longer father children.

But surgery doesn't always eliminate the cancer, says Dr. Michael Dattoli of Sarasota's Dattoli Cancer Center and Brachytherapy Research Institute. "Theoretically, if you remove the prostate gland, you should have a PSA of zero," since only the prostate produces those antigens. Not so. According to Dattoli, the vast majority of surgical patients still show advancing PSA rates years after their procedures.

"Cancers are very sneaky," he continues. "With surgery, you can only remove what you see with the naked eye. In essence, you're just peeling the organ off the structures against it." He says a growing body of evidence indicates that surgery actually disperses cancer cells into the blood stream. Occasionally, says Porter, the cancer is caught at a site where the surgeon can spare the nerves that control erection. But he believes that anyone with early disease would do just as well with two other options: external beam radiation and seed implantation.

External radiation therapy can sometimes cause red, dry and tender skin, along with hair loss, but according to the NCI, it's not as likely to damage the nerves that control erection. A new type of therapy called IMRT is so precise that, in the right hands, it can direct a beam of light around the bowel and bladder, reducing the risk of incontinence as well, to less than one percent.

IMRT is commonly used in conjunction with radioactive seed implantation, or brachytherapy, a procedure that works by inserting radioactive seeds directly into the prostate gland. Each seed is about four millimeters long and .08 millimeters in diameter (the size of the lead in a mechanical pencil). They kill the cancer by damaging its DNA, so cells die as they try to grow.

Before the procedure, an ultrasound measures the volume and size of the prostate. Doctors use the resulting image to evenly distribute anywhere from 40 to 120 seeds into the gland.

Brachytherapy is performed under general anesthesia and lasts between 60 and 90 minutes. Patients return for an X-ray that checks the seeds' placement, then follow up with a PSA blood test and rectal examination every six months.

"The side effect profiles for radiation therapy are actually very predictable," says Dattoli, who served as chief fellow in brachytherapy and radiation oncology at Memorial Sloan-Kettering Cancer Center in New York and at Cornell University's medical center before moving to Sarasota. He says doctors who are experienced with the different grades of seeds can tell a patient what he should expect and for how long, and adds that urinary side effects from radiation are often limited to the treatment period.

Brachytherapy virtually eliminates the possibility of incontinence and impotency and spares adjacent tissues and organs. Once the irradiated seeds expend themselves, they pose no risk to the body, so they require no further surgery to remove them.

Still, timing is everything. Most doctors now start with IMRT, then move on to seed implants. Performing brachytherapy first, says Dattoli, can actually increase a man's chances of developing metastatic prostate cancer (which spreads beyond the prostate to surrounding lymph nodes, other organs, or the bones) by causing cancer cells to shed into the bloodstream.

He says combination therapy with radiation first has an 80 percent success rate in patients with locally advanced cancers. Doctors supplement the therapy with anti-antigen drugs that keep testosterone (which feeds prostate cancer) from getting to the prostate. In patients with low- to moderate-risk tumors, success rates for this type of treatment exceed 90 percent.

Another advantage to trying brachytherapy (either alone or in conjunction with radiation) is that surgery can still be performed later if necessary. If an initial treatment of surgery is not successful, seed implantation can still be used. Even older patients, who are traditionally not treated at all for prostate cancer, may benefit. Porter agrees that it's not especially useful in an 85-year-old cancer patient who already has severe heart disease and diabetes. "But if he was active with no other health problems, you could make a case for treating him."

The advantages brachytherapy has over surgery are so strong that Dattoli questions why anyone would even consider such drastic measures as a first resort. After 10 years, he says, patients who complete brachytherapy or combination therapy using radiation and brachytherapy survive at the same rate as (or better than) those who had surgery.

Ultimately, says Dr. Stephen Patrice of 21st Century Oncology, treatment choice lies with the patient, depending on his tolerance for risk, age, and stage of disease. "We're living in an era when you can't be patriarchal about these decisions," he says. "Many patients are uncomfortable dealing with all the variables and want to be told what to do, but the truth is, there are many different ways to treat this disease."

Adds Porter: "The number one goal is to get an early diagnosis." Although the NCI recommends PSA testing after 50, Porter suggests men start them as early as 40. "You've got an outstanding tumor marker, so you should utilize it," he says. "[Prostate cancer] is a typically slow-growing malignancy. It can take five years to spread beyond the gland and another five years to become metastatic." If you catch it in its earliest stages, he says, "You have a choice of several very effective treatments that will not take away from your quality of life."

THE CHANGING FACE OF BRACHYTHERAPY

Although the science behind radioactive seed implants hasn't changed since the early '70s, the way it's done has. The biggest change is determining where the seeds go, says Dr. Stephen Patrice of 21st Century Oncology.

Up until six years ago, patients underwent ultrasound in the doctor's office before seed implantation. Then a computer program drew up a sort of "blueprint" for where the seeds would be inserted. When the patient returned for surgery, the seeds were implanted based upon that blueprint.

It was a good plan, but as Patrice points out, "The prostate is a mobile organ that can shift within the pelvis." When doctors realized that their blueprint could be off by as much as a millimeter by surgery time, they began developing other systems. Today, "real-time computer dose imaging" is performed in the operating room immediately before seed implantation to ensure the most accurate placement.

Another big change is the use of color-flow Doppler ultrasound to image the prostate. In use at Dattoli Cancer Center, this gives a more three-dimensional view of the gland, presenting a more accurate picture of where the cancer may lie.